Anti-ageing scientists extend lifespan of oldest living lab rat

Sima, at 47 months old the oldest living Spague-Dawley rat, was the beneficiary of blood plasma treatments scientists believe have extended her life. Photograph: handout

Scientists working on an experimental anti-ageing therapy claim to have broken a record by extending the lifespan of a lab rat called Sima.

Named after the Hindi word for “limit” or “boundary”, Sima is the last remaining survivor from a group of rodents that received infusions of blood plasma taken from young animals to see if the treatment prolonged their lives.